Connecting joint



Dec. 18, 1923.

A. o. AUSTIN CONNECTING JOINT Filed April 10 1919 "Y 1 x I Patented Dec. k18, 1923.

UNITED STATES PATENT OFFICE.

.ARTHUR O. AUSTIN, OF BARBERTON, OHIO, ASSIGNOB, BY MESNE ASSIGNMENTS, TO THE OHIO BRASS COMPANY, OF MANSFIELD, OHIO, A CORPORATION 0F NEW JERSEY.

GONNECTING JOINT.

To all whom it may concern:

Be it known that I, ARTHUR O. AUSTIN, a citizen of the United States, residing at Barberton. in the county of Summit and State of Ohio,have invented certain new and useful Improvements in Connecting Joints, of which the following is a specification.

My invention relates to the construction of joints for holding various materials t0- gether, and has for its object the provision of connecting joints having means for controlling the distribution of stresses transmitted and which shall be of improved con- 7 struction and` eiliciency.

The invention is exempliied in the combination and arrangement of parts shown in the accompanying drawings and described in the following specification. The invention is more particularly pointed out in th appended claims. f

In the drawingsf Fig. 1 illustrates one embodiment of the invention as appliedto an insulator;

Fig. 2 is a section on line 2-2 of Fig. 1;

Figs. 3, 4 and 5 are diagrammatic sectional views through diiferent `forms of joints illustrating various modifications of the invention;

Fig. 6 is a rag'mentar elevation showing still a di'erent form-'fo the invention.

In order that theA present invention may be best understood, its application to various forms of v:electrical insulators has been illustratedbut it is understood that'the invention is applicable to a large variety ot articles other vthan insulators. It is especially use-ful where one of the members connected by the joint embodying the invention is of material more or less brittle in its nature. Electric insulators are commonly made of porcelain, or other vitrous substances, and a joint constructed in accordance with the present invention is especially applicable to r material of this character.

In Fig. 1 of the drawings, the numeral 15 designatesa tubular insulator which may be made of porcelain, or other suitable material, while the numeral 16 is a metallic end cap secured to the tube 15 for connecting the tube either with the load which it carries, or with its support. The end cap 16 may 'be tapered as shown in the drawing or may' have its sides straight, as conditions may require. In my prior Patent No.

1,284,975 issued November 19, 1918 I have described a form of sanded joint for connecting parts of insulators together, and thc present invention is an improvement and amplification of the joint shown in that patent. In preparing the end 'of the in'suator 15 for its connection with the cap 16, the portion of the insulator which isto form the joint is coated with a laze, and while the glaze is yet moist, sma l grains of ma terial are distributed over the coated surface and adhere to the moist laze. The grains are preferably small partlcles of the clay of which the porcelain tube 15 is composed, for the reason that this clay has the same shrinkage in burning and afterwards will have the same coefficient of expansion as the material of the tube 15 itself. It is, of course, possible to use grains of sand, or other substances in place of particles of clay. When the insulator thus prepared is burned in the usual manner, the grains distributed over the surface become fixed to the material of the insulator by the glaze which is hardened in burning and form a roughene'd surface for the joint. As described-in mv prior patent, the points of these grains will protrude to a greater or less extent from the glaze, and before the metallic cap 16 is cemented on, a coating of some elastic material, such as wax or paraine is spread upon the sanded `surface in a manner to leave the points of the grains protruding. yThe cap is then secured in place, as shown in Fig. 1, by cement indicated at 17. which completes the connection between the cap and the insulator, as explained in the patent referred to, and the joint thus made has a. certain degree of elasticity which tends to prevent breaking of the insulator under the various stresses to which it is subjected.

In Fig. 3 of the drawings, the particles with which the insulator surface is covered, and which will be hereafter referred to as Sand grains, are Shown diagrammatically at 18. The glaze by which the grains are held to the'porcelain is indicated at 19, and the filling of yielding material is shown at 20. It will be noted from the drawings that the coating of yielding material 20 is consider` ably thicker adjacent the edge of the cap 16 and is graded toward 'the Yend of the insulator 15 until it becomes very thin at the inner end of the joint. It will thus be seen that the grains 18 adjacent the edge of the cap 16 will have their points only imbedded in the*`-` f tively rigid connection between the cap and the insulator, for the reason that practically the entire sand grains are imbedded in the cement. y Between the two ticityl of the union gradual y grades one extreme to the other.

It is thought that the purpose of from this' graded elastic joint will 4be readily apparent.'

lf there were an absolute rigid connection between the cap-16 and the insulator l5 at the edge of the cap. then the load upon the insulator would all be transmitted to the cap at this point. Illhis would place undue stress upon the cement at this point, tending to cause the joint to tail, and would also subject the material ol the insulator 15 to a greater breaking stress than that producedl by the -graded joint. llt will be readily understood that the cap 16 must grip the inpulator l-5 when a load` is placed upon the in'- sulator sufficiently tight `to prevent the insulator from slipping out of the socketi'ormed by the cap. lli' there were no yielding in the joint between the cap and the in-` sulator, the stress of the load would all be taken up at the edge of the insulator, and the grippingforce ot the cap would all fall at this point, producing in addition to the stress in the insulator, due to the load upon it, a shearing stress adjacent 'the edgeo the cap. Under tests insulators which have ri id connection with their caps are found to ail at this point and to tail along lines of the resultant between the tensional load upon the insulator and the' shearing stress lproduced by the cap. lll/'here a graded elastic joint is provided only a small portion of the load is transmitted to the cap at its outer edge and the insulatoris vpermitted to yieldv i under the tension' upon it, sc that other por-v tionsof the load aretransmltted'to the cap at the various points along the joint. Thus the stress ol the load is distributed throughout the joint, and the shearing stress on the insulator necessary to hold the insulator in place is also distributed through the length of the material l5 surrounded by the joint.

Aln Fig. 4 of the drawings, the grains 18l are graded in size from a position adjacent the edge of the cap i6 tothe inner end of the joint,4 and the' coating material 20 is alsograded in the saine manner asin F ig. 3. rl`he grading ot the grains adds to the elect produced in Fig. 3, for the reason that the large oints the elas- `1 ,aaneen f' minsat. the edge of the cap constitute enger4 struts than -the small vgrains at the L inner endl of the joint, and consequently exhibit a greater elasticitv than the smaller grains. l

ln Flg, 5 the grains 18 are shown as of uniform' size throughout the joint, and-.the

coating is also made uniform, but the cap 16 is peripherally corrugated, as shown at 21,

the corrugations increasing Vfrom the end of theiinsulator toward the edge of thecap. lnthis wa 'the 'cap itself is made elastic so that it wil yield adjacent its edgein the dithe inner end of the joint. Itwill be understood that other expedients may be used for producing a graded elastic joint between the two members connected, and that various combinations of the means ,illustrated in the drawings may also be employed.

hile the method described of securing the grains tothe insulators is the one at present preferred it willbe understood that'the grains may beheld in place by various ad'- hesive materials such as varnish for instance. and this will permit' the sandingto be placed on lthe surface of finished insulators. lt will also be apparent that the same kind of graded connection is applicable to a large variety of terms of insu ators as for instance the ordinary pin type insulators and susj pension insulators having ca and pins or) caps or pins only. The greed projections as well as the graded coating may also be applied to cit-her the metal or vinsulator member or to both, and may be used for connectin'g .two insulator memberstogether and even for connecting two metallic members.

l claim j i l. ln combination, a pair of members having `overlapping portions secured Vtogether at points distributed along said overlapping portions by connect-ing material, said material being arranged to permit an elastic movement between said members, .the

cap, thev ielding of which is .greatest at the `end of t e tongues formed by the slits 22, and gradually decreases toward -portions thereof to distribute 'the v force transmitted frompone to the otherzofslid members. l

3. In combination, a pair of members tokv be connected together, and means for form.--

ing a graded bers. j.

4. In combination, a pair of co-operating members having overlapping surfaces, one of said surfaces being provided with proelastic joint between said mem' jections thereon, means for cementing said surfaces l to one another, and means for protecting portions ofsaid projections from engagement with said cementing means, said protecting means being arranged to cover progressiveiy varying amounts of said projections along the overlapping portions of said members l l 5. A joint for connecting two members together comprising a plurality of projections distributed upon the surface of one of said members, and means for connecting said projections with a surface ofthe other of said members, said'connecting means being arranged to engage varying portions of said projecting means to form a progressively gra-ded elastic joint .between said members.

6. In combination, a member composed of relatively fragile material, an attachino member, and means for connecting said members together, said connecting means being arranged to form an elastic joint betweensaid members, the elasticity of which` Y point, along said joint.

8. In combination, a relatively fragile member and a supporting member therefor, andymeans for connectin said members to 'form joint to transmit tie stress of a load from one of said members tn the other, 'said connecting means being arranged to forma connection between said members having a progressively decreasing elasticity from .a point alon said fragile member toward the eid thereo w 9. In combination, a member having spaced projections on the surface thereof, a second member adjacent saidsurface and secured thereto by interposed'cement, and a coating of yielding material for partially covering the projections on said surface, said' coating being arranged in a progressively varying thickness over saidsurface.

l0. In combination, a member havin spaced projections on the surface thereo and a second member arranged adjacent said surface and secured thereto by connecting material, the projections on said surface being arranged in progressively varying size along said surface.

l1.' In combination, a member having spaced projections upon a surface thereof, a second member adjacent said surface and secured thereto by connecting material, the projections on said surface being progres sively graded in size along said surface, and

a `coating of yielding material on said surface for protecting portions of said projections from said Vconnecting material, said coating being arranged in progressively varying thickness alongsaid surface.

`12. In combination, a member composed of-relativel fragile material, spaced projec- ,tions distri uted over a portion of the surface of said member, a secondmemberarranged in overlapping relation to the surface of said first-mentioned member,` connecting material for securing said members together, and a coating of yielding substance between said connecting materialand the surface of said first-mentioned member, the thickness of said coating being so varied so as to protect progressively differing amounts of said spaced projections from engagement with said connecting material.

13. In combination, a member having projections distributed over a portion of its surface adjacent one end thereof, a second member arrangedin overlapping relation with said portion of the surfaceof said first-mentionedy member, and connecting material for securing the `overlapping portions of said members together, said connecting material being arranged to hold the projections on the surface of said first-mentioned member^ more firmly imbedded therein adjacent the vend of said member than at points'spad from the end thereof to provide a joint be' tween said members V1having progressively varyin elasticity along said joint.

14. n combination, a relatively fra 'le member having a securing member attac d to one end thereof, and securing means for holding said members the'rfsaid securing means being varrange to constitute anv elastically yielding joint between .said mambers which gradually decreases in elasticityfrom the extremity of said securing member toward the extremity of said relatively fragile member.

15. In combination, a relatively fra 'le member having a securingmember attac ed thereto and arranged to overlap 'a portion of the extremity of said relatively .fra le member, s aced projections upon the sur ace of said re atively fragile member, a coating of yielding materiale on said surface in yea - subjectedA to stress, the amount of yielding thus permitted being graded to vary for diderent ositions along said joint.

17. An lnsulator having an end cap thereon and means for connecting said cap to said insulator said connecting means being arranged to permit relative yielding between Said cap and insulator the amount of yielding thus permitted being greatestat the tree edge of said cap and decreasing in a direction away from said edge toward the end of said insulator.

18. An insulator having an end cap thereon connected with said insulator by a sanded joint to ermit yielding between said cap and insu ator said joint being graded to vary the amount of yielding between said members so that the amount ofyielding decreases from a. position adjacent the edge of said cap toward the end of said insulator.

19.- n insulator having a connecting member surrounding a portionof an eK- tremity thereof, spaced projections secured to' the surface ot said `insulator contiguous to said connecting member means for securing said connecting'member to the projections on said surface to form a yielding joint to permit relative movement between said insulator and said connecting member, the

points ot connection between said projecting members and said securmg means ybeing nar/acca member secured thereto, spaced projections distributed over the surface of said insulator adjacent a surface of said connecting member means for securing said projections to said connectin member and a coating of yielding material for protecting a portion of the .bases of said projections lfrom said securing means, the thickness of said coating boing varied for different positions on sald sur faces to permit different proportions of said projections to engage said` securing means, thus providing a graded yielding joint between said insulator and connecting member with the amount of yielding progressively decreasing from a position adjacent the eX- tremity of said connecting member toward the end of said insulator.

21. An insulator having a connecting member secured thereto, spaced projections distributed over the surface of said insulator adjacent a surface of said connecting member, and means for securing said projections to said connecting member said projections being graded in size to provide for different amounts of movement between said insulator, and said member at different positions in said joint. j

22. In combination, a pair of members having. overlapping portions and elastic lmeans lnterposed between said overlapping portions for securing said members t0 one another, the elasticity of said securing means ybeing graded to vary for different positions along the joint formed thereby.

ln testimony whereof I have signed my' name to this specification on this 3rd day 'of April A. D. 1919.

ARTHUR 0. AUSTIN. 

